Anaplastic Lymphoma Kinase (ALK) is a cell membrane-spanning receptor tyrosine kinase, which belongs to the insulin receptor subfamily. The most abundant expression of ALK occurs in the neonatal brain, suggesting a possible role for ALK in brain development (Duyster, J. et al., Oncogene, 2001, 20, 5623-5637).
ALK is also implicated in the progression of certain tumors. For example, approximately sixty percent of anaplastic large cell lymphomas (ALCL) are associated with a chromosome mutation that generates a fusion protein consisting of nucleophosmin (NPM) and the intracellular domain of ALK. (Armitage, J. O. et al., Cancer: Principle and Practice of Oncology, 6th edition, 2001, 2256-2316; Kutok J. L. & Aster J. C., J. Clin. Oncol., 2002, 20, 3691-3702). This mutant protein, NPM-ALK, possesses a constitutively active tyrosine kinase domain that is responsible for its oncogenic property through activation of downstream effectors. (Falini, B. et al., Blood, 1999, 94, 3509-3515; Morris, S. W. et al., Brit. J. Haematol., 2001, 113, 275-295; Duyster et al.; Kutok & Aster). In addition, the transforming EML4-ALK fusion gene has been identified in non-small-cell lung cancer (NSCLC) patients (Soda, M., et al., Nature, 2007, 448, 561-566) and represents another in a list of ALK fusion proteins that are promising targets for ALK inhibitor therapy. Experimental data have demonstrated that the aberrant expression of constitutively active ALK is directly implicated in the pathogenesis of ALCL and that inhibition of ALK can markedly impair the growth of ALK+ lymphoma cells (Kuefer, Mu et al. Blood, 1997, 90, 2901-2910; Bai, R. Y. et al., Mol. Cell Biol., 1998, 18, 6951-6961; Bai, R. Y. et al., Blood, 2000, 96, 4319-4327; Ergin, M. et al., Exp. Hematol., 2001, 29, 1082-1090; Slupianek, A. et al., Cancer Res., 2001, 61, 2194-2199; Turturro, F. et al., Clin. Cancer Res., 2002, 8, 240-245). The constitutively activated chimeric ALK has also been demonstrated in about 60% of inflammatory myofibroblastic tumors (IMTs), a slow-growing sarcoma that mainly affects children and young adults. (Lawrence, B. et al., Am. J. Pathol., 2000, 157, 377-384; Duyster et al.).
In addition, ALK and its putative ligand, pleiotrophin, are overexpressed in human glioblastomas (Stoica, G. et al., J. Biol. Chem., 2001, 276, 16772-16779). In mouse studies, depletion of ALK reduced glioblastoma tumor growth and prolonged animal survival (Powers, C. et al., J. Biol. Chem., 2002, 277, 14153-14158; Mentlein, R. et al, J. Neurochem., 2002, 83, 747-753).
An ALK inhibitor would be expected to either permit durable cures when combined with current chemotherapy for ALCL, IMT, proliferative disorders, glioblastoma and possible other solid tumors, or, as a single therapeutic agent, could be used in a maintenance role to prevent cancer recurrence in those patients. Various ALK inhibitors have been reported, such as indazoloisoquinolines (WO 2005/009389), thiazole amides and oxazole amides (WO 2005/097765), pyrrolopyrimidines (WO 2005080393), and pyrimidinediamines (WO 2005/016894).
WO 2008/051547 discloses fused bicyclic derivatives of 2,4-diaminopyrimidine as ALK and c-Met inhibitors. The lead drug candidate disclosed in the '547 application is CEP-28122, a potent ALK inhibitor with oral efficacy against SUP-M2 and Karpas-299 ALK-dependent tumors in mouse xenograft models. CEP-28122 progressed to IND-enabling studies until its development was terminated due to the unexpected occurrence of severe lung toxicity in CEP-28122-treated monkeys.

Focal adhesion kinase (FAK) is an evolutionarily conserved non-receptor tyrosine kinase localized at focal adhesions, sites of cellular contact with the ECM (extra-cellular matrix) that functions as a critical transducer of signaling from integrin receptors and multiple receptor tyrosine kinases, including EGF-R, HER2, IGF-R1, PDGF-R and VEGF-R2 and TIE-2 (Parsons, J T; Slack-Davis, J; Tilghman, R; Roberts, W G. Focal adhesion kinase: targeting adhesion signaling pathways for therapeutic intervention. Clin. Cancer Res., 2008, 14, 627-632; Kyu-Ho Han, E; McGonigal, T. Role of focal adhesion kinase in human cancer—a potential target for drug discovery. Anti-cancer Agents Med. Chem., 2007, 7, 681-684). The integrin-activated FAK forms a binary complex with Src which can phosphorylate other substrates and trigger multiple signaling pathways. Given the central role of FAK binding and phosphorylation in mediating signal transduction with multiple SH2- and SH3-domain effector proteins (Mitra, S K; Hanson, D A; Schlaeper, D D. Focal adhesion kinase: in command and control of cell motility. Nature Rev. Mol. Cell Biol., 2005, 6, 56-68), activated FAK plays a central role in mediating cell adhesion, migration, morphogenesis, proliferation and survival in normal and malignant cells (Mitra et al. 2005; McLean, G W; Carragher, N O; Avizzienyte, E; et al. The role of focal adhesion kinase in cancer—a new therapeutic opportunity. Nature Reviews Cancer, 2005, 5, 505-515; and Kyu-Ho Han and McGonigal, 2007). In tumors, FAK activation mediates anchorage-independent cell survival, one of the hallmarks of cancer cells. Moreover, FAK over expression and activation appear to be associated with an enhanced invasive and metastatic phenotype and tumor angiogenesis in these malignancies (Owens, L V; Xu, L; Craven, R J; et al. Over expression of the focal adhesion kinase (p125 FAK) in invasive human tumors. Cancer Res., 1995, 55, 2752-2755; Tremblay, L; Hauck, W. Focal adhesion kinase (pp125FAK) expression, activation and association with paxillin and p50CSK in human metastatic prostate carcinoma. Int. J. Cancer, 1996, 68, 164-171; Kornberg, I J. Focal adhesion kinase in oral cancers. Head and Neck, 1998, 20: 634-639; Mc Clean et al 2005; Kyu-Ho Han and McGonigal, 2007) and correlated with poor prognosis and shorter metastasis-free survival.
Multiple proof-of-concept studies conducted in various solid tumors using siRNA (Halder, J; Kamat, A; Landen, C N; et al. Focal adhesion kinase targeting using in vivo short interfering RNA delivery in neutral liposomes for ovarian carcinoma therapy. Clin. Cancer Res., 2006, 12, 4916-4924), dominant-negative FAK, and small molecule FAK inhibitors (Halder, J; Lin, Y G; Merritt, W M; et al. Therapeutic efficacy of a novel focal adhesion kinase inhibitor, TAE226 in ovarian carcinoma. Cancer Res., 2007, 67, 10976-10983; Roberts, W G; Ung, E; Whalen, P; et al. Anti-tumor activity and pharmacology of a selective focal adhesion kinase inhibitor, PF-562,271. Cancer Res., 2008, 68, 1935-1944; Bagi C M; Roberts G W; and Andersen C J. Dual focal adhesion kinse/Pyk2 inhibitor has positive effects on bone tumors—implications for bone metastases. Cancer, 2008, 112, 2313-2321) have provided pre-clinical support for the therapeutic utility of FAK inhibition as an anti-tumor/anti-angiogenic strategy, particularly for androgen-independent prostate cancers, breast cancers, and HNSCCs. In preclinical models of human breast cancer (MDA-MB-231) in nude rats, administration of a small molecule FAK inhibitor (PF-562,271) inhibited primary tumor growth and intra-tibial tumor spread, and restored tumor-induced bone loss (Bagi et al., 2008). Roberts et al., (2008) showed that PF-562,271 inhibited bone metastases, prevented bone resorption, and increased osteogenesis in breast and androgen-independent prostate cancer patients with and without bone metastases, supporting an additional benefit of FAK inhibition in these specific malignancies.
In summary, there is clear genetic and biological evidence that links aberrant ALK activation and constitutive activation of FAK with the onset and progression of certain types of cancer in humans. Considerable evidence indicates that ALK- and FAK-positive tumor cells require these oncogenes to proliferate and survive, and in the case of FAK, to invade and metastasize to distant sites, while inhibition of both ALK and FAK signaling leads to tumor cell growth arrest or apoptosis, resulting in objective cytoreductive effects. Inhibition of FAK also results in attenuation of tumor motility, invasiveness, and metastatic spread, particularly in specific cancers characterized by bone metastatic dissemination and osteolytic disease. FAK activation protects tumor cells from chemotherapy-induced apoptosis, contributing to tumor resistance; modulation of FAK activity (by siRNA or pharmacologically) potentiates efficacy of chemotherapeutic agents in vivo (e.g., doxorubicin, docetaxel and gemcitabine), suggesting the utility for rational combination therapies in specific cancers. ALK and FAK are minimally expressed in most normal tissues in the healthy adult and are activated and/or dysregulated in specific cancers during oncogenesis and/or during early stages of malignant progression. Consequently, the on-target effects of treatment with a dual ALK and FAK inhibitor against normal cells should be minimal, creating a favorable therapeutic index.
A need exists for additional safe and effective ALK and/or FAK inhibitors for the treatment of cancer.